Function read 

pub fn read(path: &Path) -> Result<Option<Consent>, TelemetryError>

Read the consent file. Ok(None) when the file does not exist — callers should treat that as ConsentState::Unset.

Errors

• TelemetryError::Io for filesystem failures other than “not found.”
• TelemetryError::Serde for malformed TOML or unknown schema versions.